jsonデータの取り出しについて

Question

以下のjsonデータの中の"thumbnail_src"の値を取り出したいのですが
['entry_data']['Tagpage']['thumbnail_src']
などを試したのですがとれず困っています助言をいただきたいです。
取り出しはrubyかphpでお願いします

"entry_data": {
    "TagPage": [
      {
        "tag": {
          "media": {
            "count": 3444249,
            "page_info": {
              "has_previous_page": false,
              "start_cursor": "1399991144154424181",
              "end_cursor": "J0HWEf5owAAAF0HWEf2SAAAAFiYA",
              "has_next_page": true
            },
            "nodes": [
              {
                "code": "BNtxIc0BGN1",
                "date": 1481111971,
                "dimensions": {
                  "width": 1080,
                  "height": 1080
                },
                "comments_disabled": false,
                "comments": {
                  "count": 0
                },
                "caption": "\"Ive never met a foot a hip couldn’t control” -Charlie Weingroff. Wise words from a leader in the physio and strength world. Fact: you aren’t built with flat feet and it isn’t genetic. Pronated or flat feet stem from two big factors: 1) poor control at the hip, 2) weak feet from spending too much time in footwear (and usually very shitty footwear). Flat feet bleed power and speed while putting you at risk of injury up the chain at the knee and hip. Take responsibility for your body and work on improving your foot posture\n\n#thefootcollective #feet #foot #flatfeet #running #run #foothealth #barefoot #footmobility #strongfeet #hipcontrol #footpain #plantarfascitis #injuryprevention #painfree #athlete #crossfit #injuryprevention #training #shoessuck #facts #myths @chweingroff",
                "likes": {
                  "count": 1
                },
                "owner": {
                  "id": "3263455404"
                },
                "thumbnail_src": "https://scontent.cdninstagram.com/t51.2885-15/s640x640/sh0.08/e35/15043420_224666977971103_1562121335457447936_n.jpg?ig_cache_key=MTM5OTk5MTE0NDE1NDQyNDE4MQ%3D%3D.2",

Answer 1

こういうことでしょうか。

['entry_data']['TagPage'][0]['tag']['nodes'][0]['thumbnail_src']